The successful use of dental implants has long been known and is well documented in the field. Despite successful dental implant procedures through the years, the success of the placement of a dental implant is limited by the quality and quantity of existing bone of a given patient. Due to the destructive nature of dentures to the underlying jawbone the amount of bone in many people is very limited for the placement of dental implants.
Furthermore, atrophy of the jawbone can occur when the bone is not subjected to occlusal loads. Therefore, atrophy may occur over time when a tooth is not replaced with a dental implant. As a result, when a person has been partially endentulous for a long period of time, they may suffer from an atrophic alveolar ridge that is not capable of securely supporting a dental implant. The deterioration of the alveolar ridge has severe consequences, including reducing one's ability to masticate and compromising aesthetics.
Immediate dental implant placement is ideal, but is not always an option for many patients. Preservation of the alveolar ridge is key to preventing a collapse of the alveolar bone and soft tissue, preventing a collapse of the alveolar ridge causing irregularities in alveolar form, and maintaining an oral socket after extraction for later placement of an implant. Thus, preserving existing bone minimizes the potential obstacles to implant placement created by atrophic jawbone.
Additionally, grafting bone is also a means to ensure that adequate bone is present for supporting dental implants. There are many known methods of bone grafting. Bone grafting procedures may incorporate bone graft material in order to stimulate bone growth. As viable exemplary methods, blocks of hip bone have been affixed to the jaw and freeze-dried demineralized bone protein has been used as a stimulant to cause the patient's bone cells to become active and lay down new bone onto the existing bone areas and into the new bone graft areas. Through experience and research, it has become evident that, for bone grafting to be successful, it must be given an isolated space to grow, protected from muscular pressure, tissue impingement and forces of mastication. In order to create this space, fabric-like membranes or barriers have been used over a bony defect. Although this barrier creates an isolated space from the invasion of connective tissue cells into the bony defect or bone graft area, it does not create a protected space from chewing forces or tissue pressure. It is necessary to protect the growing bone from all aspects of potential harm. Therefore, in many instances the space is created and maintained utilizing dental implants and supports including a tenting-type support screw.